Reef-
"
Onboard Intel® ULV Celeron® M 600 MHz
...
Support WinCE 5.0, XP Embedded and XP "
This machine is designed for embedded systems and would be a problem for a typical consumer. The Celeron M is designed as a low-power chip for mobile use, but that chip is about 1/8th the speed of low-end consumer CPUs these days, at best. It is also targetted to the "embedded" OSes and I'd suspect it would run the full version of XP rather slowly. Comparable to a six year old 600MHz laptop, yes, but compare the
price and I'd bet you could buy two laptops complete for less.
The Panasonic Toughbooks tend to be expensive but they are among the very few consumer-market machines that attempt real waterproofing, along with shock-mounted hard drives and other "toughening" features. If you want one computer rather than two (a spare) certainly worth considering, but I'd also agree that
buying two machines and having a "hot spare" onboard is probably the most economical and painless way to do it. Assuming, that both notebooks are identical
hardware so you can easily transfer a drive or drive image. Sometimes they are not, due to running changes in production. And laptops that are 'off lease' from a corporate source are often in great shape--but often develop cracks and other wear problems, from business users who drive them like rental cars (so to speak) since they don't have to own them.
Power
consumption will be fairly similar across any laptops with the same CPU type, and same display size. That's where most of it goes. A newer machine with a Vista-ready motherboard set will use less power, as will the Intel
Core Duo type CPUs, since they are able to power down specific subsystems that are not in use--and stretch the power further. Getting rid of spindles (motors) by running software from a solid state drive (slow & expensive) or an internal hard drive rather than a DVD/CD, also can make a HUGE difference. Unfortunately, a big bright
screen eats power, so going with the smallest
screen size that will do your job, and keeping it as dim as you can tolerate, is the way to go for
battery life.
Using a dc-to-dc laptop power supply, rather than a power brick plugged into an
inverter, of course will make a huge difference as well.